**Although the Royal Purple gear oil contains friction modifier, we highly recommend including the Ford Racing friction modifier along with the gear oil when refilling your rear end.**
Due to Hazmat regulations, lubricants/fluids cannot be shipped to APO/FPO addresses.
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For hot weather applications and applications with heavy shock load (drag racing) the 85w140 would be a good choice. Ford specified 75w140 gear oil for Mustangs starting in 1999. 75w90 is a great all around gear oil and is typically used where a compromise of shock load handling and fuel economy are of a concern.
Answered by Jonathan M. from Hewitt | Comment 0 0